In automatic transmissions of current motor vehicles, clutches for shifting gears are usually actuated hydraulically. To ensure that the gear shifts, i.e., the shifting operations, take place without jerks and go unnoticed by the driver, it is necessary to adjust the hydraulic pressure at the clutches according to predefined pressure ramps with the highest precision possible. The pressure required for adjusting these pressure ramps is supplied with the aid of hydraulic slide valves. Such slide valves are frequently actuated via an electromagnetic actuating device. The use of the electromagnetic actuating device according to the present invention in an automatic transmission of this kind is a preferred application field of the electromagnetic actuating device according to the present invention. If an electromagnetic actuating device is used for actuating a slide valve in an automatic transmission, then the electromagnetic actuating device is partially or completely immersed in the transmission fluid of the automatic transmission.
Such an electromagnetic actuating device includes an armature element, which is axially moved by energizing a coil. Transmission oil must be displaced during a movement of the armature element, which is usually achieved with the aid of a channel in or on the armature element. Transmission oil is able to flow through or along the armature element by way of the channel.
Conventional electromagnetic actuating devices include a channel for the fluidic passage of transmission oil extends through an actuating element that is pressed into the armature element, and through the armature.